(A)日常維護(hù) (B)定期保養(yǎng) (C)小修
(A)反洗 (B)進(jìn)鹽 (C)置換
(A)1、2、3號(hào)閥 (B)5、6、7號(hào)閥 (C)5、7、9號(hào)閥